The present invention relates to a method of and an arrangement for attaining a tape-protective tensioning of a tape in tape-recording devices. More particularly, it relates to a method of and an arrangement for tensioning a tape in a tape-recording device with a braking roller, a pulling roller, two sound shafts rotating with approximately equal angular speed, and at least one sound head.
Known tape-recording devices encounter the problem in that they must provide for a firmest possible abutment of the sound tape against the sound head in order to eliminate undesirable variations of amplitude during recording and reproduction, particularly when separate head systems for recording and reproduction are utilized in cassette devices. This problem particularly arises when two sound shafts are utilized, in order to attain the sufficient tape-head contact. In such a device contrary to the device with only one sound shaft, the driving force is indetermined statically. In addition, when the fixed axis of rotation normal to the tape plane extends downwardly of the tape toward the sound shaft, the tape drive is mechanically instable, inasmuch as even small deflections of the sound tape parallel to the sound shaft are automatically increased. When the fixed axis of rotation normal to the tape plane extends upwardly of the sound tape, deflections of the sound tape parallel to the axis of the sound shaft are automatically compensated. Pulled sound shafts are mechanically instable, and driven sound shafts have a stable tape position (RADIO MENTOR ELECTRONIC, 11/78-198).